Major efforts included: (1) Publishing new information on the risk of lung cancer from radon based on a joint analysis of eleven cohorts of miners; (2) publishing results of a combined analysis of three case- control studies of lung cancer risk from exposure to indoor radon; (3) completing joint analyses of risk of thyroid neoplasia following gamma radiation; (4) publishing the result that human papillomavirus accounts for much of the risk of cervical intraepithelial dysplasia in a cohort of women in Portland, Oregon; (5) completing manuscripts on study design and exposure assessment for a study of hematologic cancers following occupational exposure to benzene in China; (6) demonstrating long-term excesses in mortality and learning disabilities in adult survivors of childhood cancer; (7) testing the hypothesis that chronic fatigue syndrome is associated with certain cancers; (8) showing that consumption of meats high in heterocyclic aromatic amines induces expression of the CYP1A2 enzyme; (9) analyzing and publishing data on the effect of vitamin supplements on gastric cancer incidence, on esophageal cancer incidence, and on the progression of esophageal dysplasia; (10) assisting in the analysis of the COMMIT trial data on smoking cessation; (11) validating a model for predicting breast cancer risk, and extending the model to include mammographic density; (12) designing a survey to see if prevalences of known risk factors can account for observed geographic variation in mortality rates; (13) determining attributable risks for known risk factors for esophageal cancer, mesothelioma, stomach cancer, bladder cancer, pancreatic cancer, and non-Hodgkin's lymphoma; (14) obtaining age-specific estimates of HIV infection rates by an extension of backcalculation; (15) studying AIDS-associated cancers by linking AIDS registries with cancer registries and determining the prevalence of cancers in patients with AIDS; (16) estimating the effect of age on the AIDS incubation distribution; (17) estimating the infection curve for hemophiliacs in the Hemophilia Study Group.